Party-line telephone system.



` PATENTED APR. 28, 1907.

F. VOLLMER PARTY LINE TELEPHONE SYSTEM APPLICATION FILED NOV.22.1906.

3 SHEETS-SHEET 1 Y NGN A 7TOHNE YS INo. 851,458. PATBNTED APR. 23, 1907.

' E'. VOLLMBR.

PARTY LINE TELEPHONE SYSTEM.

APPLICATION FILED NOV. 22.1906.

` A 3 SHEETS-SHEET 2.

line

W/TNEASSES fNo. 851,458. PATENTED AI'R. 23, 1907.

- P. VOLLMBR.

PATY LINE TELEPHONE SYSTEM.

APPLICATION FILED NOV.22, 1906.

A 3 SHEETS-SHEET 3.

l -w i?- 3' lllllllllllllllmh- EI? "a8 al Illu-.Illu

ATTOHNE YS fj ditionwithin time.

l FnLToN voLLMER, or WINSTED, MINNESOTA.

PARTY-MNE TELEPHNE SYSTEM.

` Specification of Letters Patent.

:Patented April 23, 1907.

Wheat-,ion filed November 22,1906. Serial No. 344.589.

To LU whom it may concern:

Be it known' that I, FELToN-VQLLMER, a citizen of the United States, and a resident of Winsted, in the county of'McLeod and State of Minnesota, haveinvented a new and lmproved Party-Line Telephone System, of which the following is a full, clear, and exact description.` l

My invention relates to party line telephone systems of the general type represented by that described in my Patent 774,543, dated November 8, 1904and used for selective signalling between stations.

My invention further relates to providing such a system with an automatic time-controlled cut-out, whereb the system after use will return automatica ly.to its normal con- My invention further relates to certain improvements in the electricalt connections, the orrnpf various parts, and various constructiona'l` details whereby the general 4efficiency of the system is improved. p

j Reference is to be had to the accompanying drawin s forminga part of this speciiication, in wlnchsimilar characters of reference indicatecorresponding parts in all the fig-- Figure 1 isla diagram of three stations, certain mechanical parts at said stations bein shown in perspective, and stations numbere 2 and 4 being shown as in pro er condition for conversation, station num er 3, meanwhile, being shown as locked out;` Fig. 2 is an enlarged diagram of the station lnumbered 3, certain parts appearing in persplective, the mechanism lat this station being ere shown howevelyas in its normal condition, the line being inactive; Fig. 3 is an enlarged fragmentary section through the casing-showing certain movable parts, and indicatin how the latter are actuated; F ig.- 4 is an en arged section upon the line 4--4 of Fig. 3, looking in the direction of the'arrow, and showing a rear View of the gears 78, 81, and parts immediately controllable therebyforthe pu ose of effecting certain circuits usedlparticu arly in calling. v

The boardsv and 6 (see Figs-3) represent the rear and front casing walls of the instrunant at each station, and which support 'the revoluble parts. The front wallr is rovided with a circular aperture 7 mto w 'ch cular form.

fits a collar 8 supportiirgeaxed plate of cira predetermined length of` pinion 36 meshing wit v 37; the pinion 38 of this wheel last men-` A shaft 10 is journaled vwithin the plate 9 and the rear wall 5, thus being adapted to turn. Mounted 'rigidly upon this shaft is a cam 11 provided with a short flange 12, and a longer flange 13; each of these ianges is of arcuate form and rigid Aupon the cam, the flange 13 extending fromn bushing 14 of insulating material to one of the lextreme outer edges of the cam, the flange 12`being spaced a short distance from the bushing, andextending to thefouter edge of the cam.

The bushing is of insulating material, thereby enabling the ianges 11, 12 to be of metal. It is not intended for-any current to pass through them. The flanges are each adapted to engage a pin 15 mounted upon a contact ,arm 16, the latter being pressed downwardly by a leaf-,spring 17., A contact hook 18 is disposed ad]acent'to the arm.16 and is free to swing slightly, excess'of movement being prevented by limiting-stops 19 disposed uponits opposite sides. This hook 18 1s providedwith contact oints 20, 21, is made of metal, and is norma y drawn to the right, according to the view presented in Fig. 2, by means of a sprin 22.

disk 23, provided wit notches 24,v spaced apart bya distance representing 90 'or one-- uarter of .the peripheral circumference of tliedisk. Adapted to enter thenotches 24, 25 is a tooth 26,-mounted u ona 1ever-27 which is 'ournaled' at 28 an is adapted to swing. armature 29 is mounted upon the upper end of this lever, for actuating it. A gear wheel 30 is rigid upon the shaft 10. Intermediate of this gear wheel 30 andthe disk 23 is a gear wheel 31 and a ratchet wheel 32 practical connected by a sleeve 34 (see Fig-3). This gear wheel 31 and ratchet wheel 32 are loose u )on the shaft', and, ofcourse, turn as a unit, tlieir movements being independentof the movements of the'disk 23 and the gear30. Meshing with the gear 30 is another gear wheel connected ri idly with which `1s a another gear wheel tioned, meshes-with a wheel 39, the latter having a winding shaft 41 which is connectd by a spiral spring 40,With a post 42.

` The winding stem 41, bein `of ordinary con- `struction, is merely shown iagrammatically. Meshingl with the gear 31 is a gear' 43 hav.

ing ,pinions 44, 44, the pinion 44 meshing -with-a gear46 having a pinion 45. -The gear y integral with each other, being- IOO IIO

4,0 meinber.

.5 indicated in llig. 4.

which causes a pendulum 50 to vibrate.

Driven from the pinion is a gear 51 having ,a pinion 52, and meshing vith this pinion is a gear 53 having a pinion 54; the Alatter meshes With a gear 55. This gear is mounted upon roja Winding stern 56 connected by a spiral spring 57 with a post 57. .The Winding stem 56 (being of known construction) is shown diagranunatically, The escapernent Wheel 48 is driven solely by the action of the 15 spring 57, but When the disk 23 is free to rotate it turns at the same speed asthe shaft 10, though `driven independently thereof. The gear 58 is provided With a stop-pin 59 and is connected With a spirahspring 60 ze which is comparatively Weak and is also tolerably short.v l

` An arm 61 is provided with a tongue 62, bent laterally toward the gear 58, andl against which the pin 59 'may stop; this tongue 62 z 5 therefore, serves as a limiting stop for preventing excessive .movement or" thegear 58 in one direction. A pin 63 serves as a `iournal for the arm 61. 'A stub shaft 64 serves to connect the spring 60 'With the gear 58.

3o The u per end of the arm 61 is provided With a vhoo portion 65`Which rests upon a spiral cani'66', the outermost or peripheral surface i orn the latter terminating in a point 67. This earn 66 is rigid upon the shaft and is so arn 3.5x .ranged that, relatively to the rotary motion 'ci the shaft 10, the point 67 lags a trifle behind 'the outer end ci flange 12. (See Fig. 2). A brush 68 of spring metal presses upon the shaft 10 and thus serves as a contact The shaft 10 is provided with a boss 69 Which is adapted, upon the revolution of the shaft, to nia'he engagement with a contact spring 70 so as to move the sarne radially outward-or awayi'rorn the shaft, as

A contact arm 71 ispivotally mounted in the position indicazled in Fig. 4 and is adapt-v edto rest against a stop pin 72. A leaf spring 73, presses the arm 71 toward'the 5o stop pin. rlhe contact spring 70 is provided with a tooth 75 against which the outer end ofthe contact arrn 71 may rest. A stop pin 7 6 .prevents undue movement or' the ontact spring 70.V Encircling the shaft 10 is va sleeve 55 './7 of insulating material. naled upon this sleeve and is provided with a pin, 7 9 and also Witha hub -8f), the latter ex A gear '.78is jcur.

l tending along the sleeve 7 7 for the purpose of ,affording a good bearing for the contact 5 5 the gears 81, 7 8, Will be rotated as will 1neun-p.

48. The latter Works va The gear 81 meshes with 'thel senese derstood from Figs. 3 and Li. The gear 78 is providedwvith a contact spring Tvillen the crank 88 is moved to its norinal position, indicated by zero, (see Fig. 4.-), the in 79 raises the arm 71 slightly, and enab es the tooth 75 to snap under it, and to support i'1 out of engagement with 'the stop pin 72, thereby making an electric circuit 'through the arm 71 and the spring 85.

A contact arm 85", mounted rigidly upon 'lone end of the 'shaft 10, carries a contact spring 85a. The plate 9 ofinsulating mate rial immediately oe-.ck of the arm 85?), is provided with a number of contact pins 86, 87, 88, extending entirely through the plate as will be seen from the sectional view in Fig. 8. These contact ins may be engaged from the iront side'loy t e contact spring 85a, and also from the back by the contact spring 85. A contact pin 87, located' just above the pin 86, is connected by a Wire 87b,`with acontact pin 87', the latter being disposed a little dis tance a vay, and at thetcp of the dial.

The various stations all equipped alike with the exception that at each station a particular wire 89, 90 is connected with a particular contact pin 87, 88, each station thus having' anindividuality with respect to the connection of 4its particular Wire 89,' 90, with indicated in Fig. 1', the station 2 at the lett has the Wire 89 connected with its contact pin 87, While at statien'S the Wire 90 is con- .'nectfed, not with the contact pin 87, but with -thecntact pin 88'; and at station 4, a Wire 91 is connected with a contacu pin 8Q"-.

' t each station a casing or board 92 is provided for the urpose of supporting' sorne of the parts. Ti e-magneto generator' 93 is of the usual construction. 'A switch hook is shown at 94 and' is adapted to'support areceiver 95. The local cattery circuit 96 is equipped inthe usual manner and is pro vided with a primary transformer Winding 97, which acts iiiductively' 'on a secondary winding 98. Abnormal contacts 9.9, 100, are closed when the switch hook 94 rises into its abnormal position.

Connected with the ground 101 is a ground .'Wire 102 which joins a wire .103. The latter is connected by a vlrire 104 with the generator 98, the latter being in communication with the switch hook Q4, and' from the switch hook 94a 'Wire 165 leads upwardly to the vided with a movable armature 11i anda its'particular contact pin. For instance, Vas c The relay v111y p'ro-v lside of the limiting stop 62.

contact 115, the latter being connected by, a Wire 116 with a wire-110. From the armature 114 a wire 117 leads to a bell magnetv 118,'the latter being connected by a wire 1,19 with a clapper contact 120 operating the clapper, which strikes the twin gongs 121. An insulating link 18a Fig. 2 connects the hook 18 with the clapper. The contact- 120 is connected by a wire 122 with the Wire 109. Connected with the wire 112 is a wire 124 leading to a releasing magnet 125, the 'latter being connected b a wire 126 with the contact pin 87 c exten ing through the plate 9as above described.

The operation of my system is described as follows: We will first suppose that the line is inactive and that each station is in its normal condition as indicated in Fig. 2.' Each contact point 20 of the contact hook 18 and is supported, for the time being, independ" ently of the cam. 11. In other words, each pin 15 has 'ust dropped over the rear or u per end of t e flange 13. The positlon of t e shaft 10 is now such that the disk 23 cannot rotate, its notch 24 resting upon the tooth 26. The hook 65 of the arm 61 rests upon a comparatively thin portion of the cam 66 thus causing the gear 58 to be temporarily out of mesh with the pinion 44, the spring 60 maintaining the gear 58 in such a position that the pin 59 carried by this gear engages the under The contact arm4 85", which serves also as an indicating needle as above explained, `now rests upon the contact pin 87a. Thereceiver 65 rests as usual, upon the switch hook, and the battery circuit and all the other circuits are open. Everything is motionless exce t the train of gearing consisting of,` the fol owing members.: spring 57, gear 55, propelled thereby, pinion 54, gear 53, pinion 52,gear 46, pinion 47, escapement wheel-48 (driving the pendulum 50) also pinion 44 driven fby gear 46 and driving gear 43 which turns which is ractically,l integral therewith as above exp ained; hence, as the disk 23 is stationary, the ratchet wheel 32 merely turns subscriber at station 2 the subscriber at station 4 grasps the handle 84 and turns the crank 83 to zero, (if it is not already there) and then to the second ordinal ofthe series. If he had wanted station 5, he would have moved the crank 83 to the ith ordinal. turnin Athe crank to theproper ordinal, the

- gear-w eel 78 is turned to the same extent in the opposite direction, so that the contact spring85 carried by it enggges the rear face s pm extending of the contact pin 87, t

nearv 31, and consequently turns ratchet wheei-a32,

Iny

through the plate 9 as'elsewhere explained. During this movement of the contact spring 85, the arm 85? does not move for the reason that the gear-wheel 78 rotates independently of the arm 85h. The contact sprin 85now resting on the contact pin 87, the ca ling subscriber next actuates'his generator 93;v An alternating'current is thus sent over the fol* lowing circuit:l ground 101, wire 102 of station 4, wire 103, wire 104, generator 93, wire 105, contact arm 16, tooth 20 (u on which the latter now rests; see Fi 2)), contact hook 18, wire 123, wire 112 iine 113 to all stations, tlence downward from the line at Aeach station', through wire 112 and wire 124 and (being unable to enter wire 123 because the generator-.circuit not being inuse is open as usual) through releasing magnet 125, wire 126, contactA pin 87, wire 87", contact pin 87a, contact arm 85b (still resting oathis contact pin) shaft 10, brush 68, wire 106, wire l03,-wire 102, to ground 101, thence return vingthrough ground to calling station. .The circuit just traced, bein duplicated at each ci the stations, is a so-ca ledy bridge circuit based upon the use of an excess ofpower, so that regardless of considerable waste of cur- Vrent through a small number of stations, there is su'flicient energy to actuate all of the magnets 125 upon the,- entire line. At` the calling station (in this instance, station 4), tli'e releasing magnet 125 is energized lliya shunt circuit from the wire 112; as follows:

wire 11.2, wire 124, 'releasing magnet 125, 'wire 126, contact pin 87,contact arm 85", shaft 10, brush 68, wire 106, wire 104, generator 93, wire 1.05, contact arm 16, contact 'hook 18,- wire 123, wire 112, to ,Wire 124, lwhence the circuit'began,` in.other. Words in Aenergizing the main line by means of Wire 112 part of the current from. this wire slits oii" and passing through the magnet 125 returns to the generator. It will thus be seen that every releasing magnet 125 uponthe entire "line, including the calling station, is energized; each larmature 29 is thereupon rattracted and the withdrawal ofeach tooth 26 -allows the several disks 23 to begin turning under the impulse of the gears 35, 37, 39, Vtheir connections and spring 40; disk 23 turns at the same speed as the gear 31 and presses the pawl 33 into the teeth of the ratchet wheel' 32. This4 occurs. notwith- 'standing the fact that the ratchet. wheel 32 is driven by the lower train ofgearing actuated by spring 57; for' the time being therefore,

-the pressure ofthe pawl 33 upon the ratchet l wheel 32 causes the disk 23 and ratchet wheel 32 together with the ears 30, 31,to rotate as 1f locked rigidly toget er. v. The shaft 10 now turns until the tooth 26 clicks into the notch 25 that is .to say, the shaft and all parts mounted thereupon turns a distance re resenting three-quarters of arevolution. In( oing this, the `contact arm 85b passes i-n succession over IOO each. of the contact pins 87, 38, stop ing at the contact pin 87C. At the instant .f ien the arm 85h passes over the contact pin 87, theI ig. 3; position of arm 85b indicatedby dotted lines). There is thus completed, at this particular instant only, a battery circuit which cannot aii'ect any station excepting 'station 2, this battery circuit being as follows: ground 101 at station 4, wire 102, wire 103, wire 106, brush 68, shaft 10, contact arm 85h, contact spring 353', Contact pin 87, contact spring 85, gear wheel 78, hub 80, contact spring 70, contact pawl 71 (for the moment in engagement with contact spring 70), wire 109, battery 108, wire 110, relay 111, wire 112, to line 113; from line 113 the current cannot get to the ground except at station 2, for the reason that this is the only station in which the contact pin 87 is provided withawire. The current hows to the ground at station 2 as follows: wire 112, relay 111, wire 110, wire 89, contact pin 87, contact spring 85a, .contact arm 85h, shaft 10, brush 68,' wire'106, wire 103, wire 102, to ground where the circuit started. The relays 111 at stations 2 and l being thus energized, the following local circuit is completed at each of these stations: battery 108, wire 110, wire 116, armature 114, (now attracted by magnet 111), wire 117, bell magnet 118, wire 119, contact 120, wire 122, back to battery 108. This rings the bells atstations 4 and 2, the duration of the ring being quite short. The shafts 10 continuing their revolutions so as to complete the three-quarter turn, the other several stations are left in the condition indicated in Fig. 1. That is to say,at stations 2 and 4 the contact arms 16 rest now u on the 'lower contact points 21, while at a'l of the other stations, for instance, station 3, the arms 16 are raised out of engagement with the contact oints 20. The parties vnow take down their respective receivers and may talk over the following circuit: ground 101, Wire 102, secondary winding 98, receiver 95, switch hook 94, wire 105,l contact arm 16, contact hook 18, Wire 123, wire 112, to line; thence at station 2, through wire 112, wire 123, hook 18, contact arm 16, Wire 105,

switch hook 94,',receiver 95, secondary winding 98, and wire 1,02, back to ground 101. The circuit j ust traced `is the main or secondary circuit of the line and is energized inductively by the local circuit96 of either stationin the manner well known. The con- 'versation being finished, either party ac uates his generator 93 this completes the following circuit; ground 101 at station L1, wire v102, wire 103, wire 104, generator 93, wire 1405, contact'lever16, contact point 21, consenese 'tact hook 18, wire 123, wire 112,' to line,

thence to all of the other stations; Wire 112, Wire 124, releasing magnet 125, Wire 126, Contact pin 87C, contact spring 85a, contact arm 85h, shaft 10, Wire 106, Wire 103, Wire 102, to ground 101. The circuit just traced energizes the release magnet 125 at all stations including the one thus ringing ofi, say station No. 4. shunt from the circuit at wire 112, station 4, energizes vthe release magnet 125 at that station. This shunt circuit is as follows: wire 112, Wire 124, releasing magnet 125, wir'e 126, contact pin 87, contact spring 85a, contact arm 85h, shaft '10, brush 68, wire 106, Wire 104, generator 93, Wire 105, back to wire 112, whence the shunt circuit started. The several bridge Wires being thus energized, the several armatures 29 are attracted and the several disksy I 23 are set in motion. The disks then make a quarter turn, each disk turning its proper shaft 10 to that extent. Hence, at each station the arm 85b is brought to rest upon the contact pin 87a, the contact arm 16 is brought to a position where it rests upon the tooth 20, and generally speaking, every part is in the position indicated in Fig. 2. The hook now occupies its lowermost position (see cam 66, Fig. 2), the arm 61 is down, the

gear 58 is out of mesh with the pinion 44, and the spring 60 has brought this gear 58 into such position that the pin 59^rests against the stop 62. Suppose however, that the subscribers do not finish their conversation within a reasonable, 'predetermined time, say for instance, five minutes, or neglect to ring off. In this event the gear wheel 58 being in mesh fwith the pinion 44 for the time being, and being constantly turned thereby reaches such a position that the pin 59 presses the lever 27 to the left, thereby disengaging the tooth -26 from the notch 25. This releases the disk 23 and allows the shaft 10 to turn until stopped by the entrance of the tooth 26 into the notch 24; in other words, the shaft and all parts mounted upon it, turn one-fourth of a revolution. This restores the shaft to its normal condition IOO shown in Fig. 2, and having the status described above at the beginning. of the operation.

It will beunderstood that the parts shown in Fig. 4 are so arrangedthat'if they happen to bein normal position as indicated in Fig. 2, and the handle 83 -is turned as above described, preparatory to calling, if the handlb be left in any position except at zero the arm 71 is not left in contact, with the contact spring 70. When the handle is turned to zero, thearm 71 is lifted by the pin 79 and rested upon the shoulder 75, but the circuit through the releasing magnets 'is still open and must r ain so, as long as the shaft 10 is at rest. Inflollows therefore, that the releasing circuit cannot be closed except as the contact arm 71, thus still above described, no matter in what position a subscriber may leave the handle 88. When the shaft 10-is set in motion, the boss 69 onA shaft 1 0 lifts the contact sprin 70 and drops Ieaving the releasingcircuit open. This circuit can never be closed, therefore, except in the orderly mannerabove set forth in detail It will be noted therefore, that my syst. In embodies the feature of a cut-out, a selective function, an alarm controllable by a relay, batteries having open circuits, and various factors ,adapted to promote safety, convenience and economy. It will also be noted that the gear Wheel 58 is controllable by clock-work and allows the callin and called stationsto remain in condition or talking, without interruption or being overheard by other stations, for a limited period only, preferably five minutes; nevertheless conversation may continue for a longer period ifthe line should not be wanted by others on the line, as either subscriber may call a second or a third time.

The system admits of special use in connection with measured service.

Having thus described my invention I claim as new and desire to secure by Letters Patent:

1. In a party-line telephone system, the combination of a revoluble shaft, contact mechanism to be opened and closed thereby,

a talking circuit to be completed and broken by movements of said contact mechanism, a train of clock-work, mechanism controllable by said train of clock-work for releasing said revoluble shaft, and meansfor turning said revoluble shaft.

2. In a party-line telephone systenuthe combination. of' a talking circuit, contact mechanism for controlling the same, clockwork for actuating said contact mechanism,

luble shaft for actuating said contact mechanism, 'means for holding said revoluble shaft in a predetermined position for the purpose of allowing conversation to proceed over said talking circuit, and time controlled mechanism for releasing said revoluble shaft. y

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

F ELTON VOLLMER.

Witnesses WM. RoHLING, C. R. VOLLMER. 

